The present application is the national stage under 35 U.S.C. 371 PCT/ES00/00029, filed Jan. 25, 2000.
1. Field of the Invention
The present invention relates to the regeneration of bone tissue within surgical practice in general, and especially in oral surgical practice, by filling a bone cavity with a graft material which stimulates and accelerates the regeneration.
2. Description of related Art
Until the present moment, various graft materials have been used, and the nature of the material used determines how bone tissue is regenerated.
In this respect, several authors have published studies and reports about the use of different materials and/or compounds for this purpose.
Yarnazaki Y, Oida S, Akimoto Y, Shiosa S in Clin Orthop Related Res (1988: 234; 240-9) refer to the use of a bone-derived morphogenetic protein bound with plaster of Paris (calcium sulphate) for this type of regeneration.
Traditionally, both autologous bone and demineralised bone (DFDBA), either alone or combined with other elements, have been used to constitute graft material for bone cavities within this technique.
Moreover, this type of graft material has also been protected with different barrier materials in order to prevent adjacent tissues encroaching on the graft material.
Various materials have been used as barriers for the aforementioned graft material, the most popular being a poly-tetrafluoroethylene membrane, despite creating problems due to the fact that it is not biodegradable and can cause infections in certain cases. In addition to this, since it is generally used in a solid form, it must be trimmed during surgery to conform to the graft recipient site and then sutured in place.
The U.S. Pat. No. 5,366,507 specifies a composition which combines a graft material based on a mixture of dermineralised bone and calcium sulphate, and a barrier material consisting of calcium sulphate. This composition does not greatly improve upon the previous techniques.
Various studies have shown that the growth factors found in the blood encourage bone formation, especially the growth factors P.D.G.F. and T.G.F.B.
However, the practice of extracting and concentrating such growth factors in an outpatient setting is unknown, as is the clinically observable and measurable effect of these growth factors.
In a particular embodiment of the present invention, a gel of plasma rich in growth factors (P.R.G.F.) as a graft material for the filling and regeneration of bone in cavities and bone defects, or for regeneration.
The present invention provides a method to obtain and prepare the factor rich plasma for out patient use.
The present invention further provides a method and a composition for the regeneration of bone tissue which represents an improved rate in the regeneration and which may be administered rapidly to the patient.
In yet another embodiment of the present invention, there is provided a kit to be used for the preparation of the P.R.G.F. gel.
Advantageously, the use of P.R.G.F. gel for the regeneration of bone tissue brings acceleration and benefits to the bone regeneration which are greater than those of techniques currently in use, as well as quicker and more predictable healing of the soft tissues, as will become apparent below from the results obtained.